BILLY

History

Severe Tropical Cyclone Billy developed during the 1998–99 Australian region cyclone season, forming as a tropical low on 2 December 1998 in the Joseph Bonaparte Gulf and Timor Sea area. The system tracked southwestward, briefly crossing the northern Kimberley region of Western Australia as a developing low before moving back over open ocean waters, where it reached cyclone intensity on 3 December. Billy underwent rapid intensification between 4 and 6 December as it moved west-southwest into favourable atmospheric conditions with low vertical wind shear, reaching Category 4 severe tropical cyclone status on 5 December with a minimum central pressure of approximately 945 hPa and peak sustained winds of around 175 km/h. The cyclone developed a well-defined eye visible on satellite imagery at its peak. From 7 December onward, increasing upper-level wind shear and cooler sea surface temperatures caused steady weakening. Billy fell below cyclone intensity on 9 December as it moved into the mid-Indian Ocean.

Because the storm's core remained offshore after its initial passage over the sparsely populated Kimberley coast, no structural damage was reported on the Western Australian mainland and there were no casualties or injuries. Offshore oil and gas operations on the North West Shelf took precautionary measures, and shipping lanes in the region were temporarily rerouted in response to large swells generated by the cyclone's wind field.

Sources: Bureau of Meteorology report Wikipedia